Vertical Subsurface Flow CW's: Dimensions
Rule of thumb: 3 - 5 mē per p.e.
The depth of the actual percolation column should be at least 0.6 m. A common composition of a VSSF is as follows: distribution layer 0.2 m, percolation column 0.8 m and drain layer 0.2 m.
The hydraulic loading rate should be at least 25 l/mē.d, with a maximum of 60 l/mē.d. These values are only applicable for domestic wastewater. If water is treated that is higher in organic strength, recirculation can be necessary.
Slope of the berms of the reed bed should be higher than 1:1, ideal is a value between 2:1 and 5:1.